RAIPUR: A day after a home-theatre wedding gift exploded, killing a groom and his brother in Chhattisgarh's Kabirdham district, police on Tuesday arrested the bride's former lover for the bizarre yet spine-chilling murder.Hemendra Maravi and his brother Rajkumar of Kabirdham's Rengakhar village were killed in the blast while setting up the home theatre, unaware that it was an IED. Seven members of the family, including a 1.5-year-old child, were injured.There are very few such instances in the country - in January 2018, a sacked postal employee couriered a radio bomb that killed an unintended target in MP's Sagar, and the next month that year, a former college principal was arrested for sending a parcel bomb that killed a groom and his grandmother in Odisha's Patnagarh.Police identified the Kabirdham home-theatre bomb suspect as 33-year-old Sarju Markam, who is married and has two children. He was arrested from Balaghat in Madhya Pradesh, around 100km away, on Tuesday.Police said that Markam was in a relationship with a 29-year-old woman and insisted that she become his second wife. Her family would have none of it and fixed her wedding with Hemendra, 30, who had no clue about this history, said police.Furious at this, Markam decided to take revenge, said police. Investigators said that he bought a home-theatre system, stuffed 2kg of explosives inside the speakers and rigged the IED to explode on electrical contact. Markam used to work in the blasting department at a crusher plant in Indore, so he could lay his hands on explosives and knew how to put together a bomb, said police.Markam went to the wedding on March 31, presented the gift to a family member without being recognised, and quietly slipped out, said an officer. The family opened the 'gift' three days later, on Monday, and were thrilled to see a home theatre although the package had no name or address. It exploded as soon as they plugged it in. The groom was killed on the spot and his brother died in the hospital.